Question: $ 4^{-3}$
$= \left(\dfrac{1}{4}\right)^{3}$ $= \left(\dfrac{1}{4}\right)\cdot\left(\dfrac{1}{4}\right)\cdot \left(\dfrac{1}{4}\right)$ $= \dfrac{1}{16}\cdot\left(\dfrac{1}{4}\right)$ $= \dfrac{1}{64}$